In order to control the indoor climate in a building are these buildings usually provided with a heating and/or cooling system, e.g. an air conditioning system such as a Heating and Ventilating Air Condition (HVAC) system or a liquid based radiator system.
A HVAC system comprises a number of different parts such as fresh air inlets admitting fresh air to enter the ventilation system, a fan unit in order to create an air flow in the ventilation ducts, an air temperature conditioning element and an air delivery unit located at the outlet in the room. The air delivery unit may for example be an induction unit in which air flowing out of nozzles, slits or the like creates an induction causing ambient air in the room to co-circulate with the fresh air. The combined air flow may pass through the air temperature conditioning element, e.g. a heat exchanger, which thus may be located in the air delivery unit. The system may further comprise features such as dryers or dampers in order to condition the humidity of the air.
A liquid based radiator system is in general comprised of numerous radiator units placed in different rooms to which the temperature conditioning liquid, in general water, is provided. The liquid is distributed from a central heating unit to be circulated through the radiator units and thereafter returned to the central unit. These systems are in general used for heating purposes and the heat is generally transferred to the air in a room by natural convection of the air in the room. There is also an increased convection from the heating of the air close to the radiator causing the heated air to flow upwards and thus increasing the heat transfer to the air.
In order to provide a desired control of the air temperature from these systems is the control of the temperature in the heat exchanger for the HVAC-system and the radiator for the radiator system essential. In general comprise these devices a temperature regulating media, e.g. water, which is circulated through the device. In many cases may there be at least two sources of temperature conditioning liquid, e.g. a flow of hot water and cold water for the HVAC-system and possibly two heating flows having different temperatures for the radiator system. Hence, there may be a desire to control which flow that shall enter a certain radiator or heat exchanger or group of radiators or heat exchangers. In many cases is the air temperature conditioning device provided with only one circuit for the temperature conditioning liquid flow. In such a design is the inlet to the single device or group of devices controlled by valves to receive and return a flow from either a first or a second temperature conditioning liquid supply. The flow is thus controlled via first and second separate valves for the hot side respectively the cold side. Likewise, the outlet is connected via third and fourth valves to return flow conduits connected to the hot respectively cold side. The flow may thus be controlled to provide a first temperature conditioning by opening the inlet and return flow valve for the first temperature conditioning liquid while valves for the second temperature conditioning liquid supply are closed and a second temperature conditioning liquid may be provided by closing the valves for the first temperature conditioning liquid and opening the valves for circulating the second temperature conditioning liquid supply. This function may be achieved by the use of two separate 3-way valves. However, the same control may be achieved by using a 6-way valve in which the inlet and outlet of the first temperature conditioned liquid is connected to first inlet and outlet openings in the valve and the inlet and outlet of the second temperature conditioned liquid is connected to second inlet and outlet openings in the valve. The valve is further provided with inlet and outlet openings connecting it to the temperature conditioning circuit provided in the heat exchanger. This valve is exemplified in an embodiment by Belimo wherein two 3-way valves are super positioned on top of each other as shown in FIG. 1 such that a 6-way valve is constructed. In the following will this valve be exemplified how it may be used in for example a HVAC system comprising a heating circuit for supplying a heating liquid, a cooling circuit for supplying a cooling liquid and an air treatment unit.
In FIG. 1a is the valve 1 shown when it is in a first mode (I) and configured to provide a heat flow. In this first mode (I) is the upper right connection 101′, connected to the outlet of a heating circuit (not shown), open. A heat flow may thus be guided in the valve 1′ from the upper right connection 101′ to the upper central connection 105′ which is connected to the inlet of an air temperature conditioning circuit (not shown),e.g. a heat exchanger in a HVAC unit. The heating liquid flows through the air temperature conditioning circuit and returns to the valve 1′ at the lower central connection 106′. The flow is guided in the valve 1′ from the lower central connection 106′ to the lower right connection 102′ which is connected to the inlet of the heating circuit such that the heating liquid will be recirculated to the heating circuit where it will be reconditioned (heated). In this first mode (I) are the upper left connection 103′ and the lower left connection 104′ closed.
In order to change the function from heating to cooling, the valve may be turned 90 degrees clockwise such that the valve 1′ will be in a second mode (II) configured to provide a cold flow through the air temperature conditioning circuit. When the valve is turned 90 degrees will the upper and lower right connections 101′, 102′, for connecting the heating circuit to the air temperature conditioning circuit, be closed. The turning will also cause the upper left connection 103′, connected to the outlet from a cooling circuit (not shown), to open and be connected to the upper central opening 105′, i.e. the inlet of the air temperature conditioning circuit. Likewise, the lower left connection 104′, connected to the inlet of the cooling circuit, will be opened and connected to the lower central opening 106′, i.e. the outlet from the temperature conditioning circuit. The air temperature conditioning circuit will thus be connected to the cooling circuit such that a recirculated cooling flow may be provided. Hence, the change over from providing a heat flow in order to heat an air flow in the HVAC system to provide a cooling flow may be effectuated by a single turn of one actuator of the 6-way valve. Hence, the idea is to use a change over valve which may allow either (or none) of the circuits to be connected.
Hence, there are several ways of providing a system for controlling the flow through an air temperature conditioning unit in a temperature conditioning system.